<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    td{
      height: 100px;
      width: 100px;
      border: 1px solid #000;
      text-align: center;
    }
  </style>
</head>
<body>
  <form>
    <table id="table">
      <tr>
        <td>单元格1-1</td>
        <td>单元格1-2</td>
        <td>单元格1-3</td>
      </tr>
      <tr>
        <td>单元格2-1</td>
        <td>单元格2-2</td>
        <td>单元格2-3</td>
      </tr>
      <tr>
        <td>单元格3-1</td>
        <td>单元格3-2</td>
        <td>单元格3-3</td>
      </tr>
    </table>
  </form>
  <script>
    const tab = document.querySelector('#table')
    tab.addEventListener('click' ,function(e){
      
      if(e.target.tagName === 'TD'){
       const sum = e.target.innerHTML
        console.log(sum);
      }
    })
  </script>
  
</body>
</html>